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class Program
{
    const int N = 8;

    static void Main(string[] args)
    {
        int count = 0;
        int[,] board = new int[N, N];

        //Initialize the board array to 0
        for (int i = 0; i < N; i++)
        {
            for (int j = 0; j < N; j++)
            {
                board[i, j] = 0;
            }
        }

        //Initialize the pointer array
        int[] pointer = new int[N];
        for (int i = 0; i < N; i++)
        {
            pointer[i] = -1;
        }

        //Implementation of Back Tracking Algorithm
        for (int j = 0; ;)
        {
            pointer[j]++;

            //Reset and move one column back
            if (pointer[j] == N)
            {
                board[pointer[j] - 1, j] = 0;
                pointer[j] = -1;
                j--;

                if (j == -1)
                {
                    Console.WriteLine("all possible solutions to N–Queens problem are done");
                    break;
                }
            }
            else
            {
                board[pointer[j], j] = 1;
                if (pointer[j] != 0)
                {
                    board[pointer[j] - 1, j] = 0;
                }

                if (SolutionCheck(board))
                {
                    j++;//move to next column
 
                    if (j == N)
                    {
                        j--;
                        count++;
                        Console.WriteLine("Solution" + count.ToString() + ":");
                        for (int p = 0; p < N; p++)
                        {
                            for (int q = 0; q < N; q++)
                            {
                                Console.Write(board[p, q] + " ");
                            }
                            Console.WriteLine();
                        }
                    }
                }
            }
        }

        Console.ReadLine();
    }

    public static bool SolutionCheck(int[,] board)
    {
        //Row check
        for (int i = 0; i < N; i++)
        {
            int sum = 0;
            for (int j = 0; j < N; j++)
            {
                sum = sum + board[i, j];
            }

            if (sum > 1)
            {
                return false;
            }
        }

        //Main diagonal check
        //above
        for (int i = 0, j = N - 2; j >= 0; j--)
        {
            int sum = 0;
            for (int p = i, q = j; q < N; p++, q++)
            {
                sum = sum + board[p, q];
            }

            if (sum > 1)
            {
                return false;
            }
        }

        //below
        for (int i = 1, j = 0; i < N - 1; i++)
        {
            int sum = 0;
            for (int p = i, q = j; p < N; p++, q++)
            {
                sum = sum + board[p, q];
            }

            if (sum > 1)
            {
                return false;
            }
        }

        //Minor diagonal check
        //above
        for (int i = 0, j = 1; j < N; j++)
        {
            int sum = 0;
            for (int p = i, q = j; q >= 0; p++, q--)
            {
                sum = sum + board[p, q];
            }

            if (sum > 1)
            {
                return false;
            }
        }

        //below
        for (int i = 1, j = N - 1; i < N - 1; i++)
        {
            int sum = 0;
            for (int p = i, q = j; p < N; p++, q--)
            {
                sum = sum + board[p, q];
            }

            if (sum > 1)
            {
                return false;
            }
        }
        return true;
    }

}